fuel (ethanol) from sawdust

stoker · Post by **stoker** » Mon Mar 13, 2006 11:00 am

has anyone done this yet?
how much can 1l of H2SO4 convert?

Nichevo · Post by **Nichevo** » Mon Mar 13, 2006 1:39 pm

I ran across this article awhile ago, but I didn't really investigate it.
Disclaimer: I am not a chemist! But I will give it a shot. I'll show my math for the real chemists to critique.

Cellulose is a polymer that has a formula (C6H10O5)n, which would require two hydrogen to saccharify on link. Since H2SO4 is polyprotic you could theoretically get a 1 to 1 ratio. So 18mol/l H2SO4(+ 1/2 O2/mol???) * 1/1L C6H12O5 = 18 moles simple sugar. Since 1 mole C6H12O6 => 2 CO2 + 2 C2H5OH, thats 32 moles of the good stuff. 32mol * 46g/mol = 1472 grams or 3 pounds. So the volume would be: 1472g / 0.8 g/ml == 1840 ml

So assuming %100 efficiency at every stage the theoretical yield is 1.84L of ethanol per 1L of 18mol H2SO4.

LeftLaneCruiser · Post by **LeftLaneCruiser** » Mon Mar 13, 2006 3:22 pm

Have read it too already a while ago.
But i can't find the strong Sulfuric acid anywhere at a reasonable price. Only thing yet was a 0,5 ltr. bottle at more than 8 euro's...

That's more expensive than Stoli

KJH

Nichevo · Post by **Nichevo** » Mon Mar 13, 2006 4:35 pm

LeftLane: This is more feasible for mass production of fuel. You would probably be purchasing this stuff by the barrel or tonne for a lot cheaper. Thats what I would do anyways, it would also require a continuous still. But ethanol fuel doesn't need any stabilization so, fuel storage safety issues aside, it would make sense to do big bulk runs.

LeftLaneCruiser · Post by **LeftLaneCruiser** » Tue Mar 14, 2006 3:58 am

Nichevo,
Offcourse you're right.
i'd like to try the process as an experiment. But i don't have the time, capacity nor the money to handle that stuff by the barrel.

KJH